An investigation of the contribution of Single Photon Emission Computed Tomography to the diagnosis of skeletal metastases using bone scan in the African context

[摘要] ENGLISH ABSTRACT:Planar bone scintigraphy is highly sensitive but it may not be sensitive enoughto detect subtle lesions in complex bony structures such as the spine. Theaccurate anatomic localisation of lesions in regions such as this is also limitedusing planar images. Single Photon Emission Computed Tomography (SPECT)results in a higher lesion contrast resulting in an improved sensitivity for thedetection of subtle lesions. SPECT also enables improved lesion localisation,often valuable in distinguishing benign from malignant disease in the spine.A number of previous studies have demonstrated that the addition of SPECT ofthe spine significantly enhances the value of bone scintigraphy for the detectionof bone metastases compared to planar imaging alone. These studies werehowever not done in the African context where patients typically present withmore advanced disease.In a retrospective study of 576 patients with known primary tumors sent to ourinstitution for bone scintigraphy for the diagnosis of bone metastases, weevaluated 119 patients in whom both planar imaging and SPECT wereobtained. The studies were graded for the probability of metastatic disease, andthe number of spinal lesions was determined with and without SPECT. Theinfluence of adding SPECT on the interpretation of the study was determined interms of the reported probability of metastatic disease, the exclusion and confirmation of metastatic disease, the decisiveness of interpretation, and thenumber of spinal lesions.The addition of SPEeT resulted in a statistically significant change in theinterpretation of studies, although the actual numbers of patients affected wererelatively small. SPEeT resulted in a more decisive interpretation of bonescintigraphy. There was a significant increase in the number of spinal lesionsdetected after the addition of SPEeT.It was concluded that although the use of SPEeT is ideal, acceptable resultscould be achieved using planar imaging alone in this patient population. This isparticularly relevant in the African context, where SPEeT is often unavailable orscarce and in great demand.

[发布机构] Stellenbosch University